The care of hospitalized patients has evolved markedly in the last decade. Shifts in surgical and medical care to outpatient settings and pressure to reduce costs have increased the acuity of hospitalized patients and the need for improved clinical efficiency and care quality. In part due to these pressures, many hospitals have redesigned their inpatient services so that dedicated inpatient specialists ('hospitalists') provide inpatient care to medical patients. In addition, hospitalists also direct care of patients on non-medical (i.e. surgical) services at many sites. Growth of this new role, termed 'comanagement,' is paralleling that of the hospitalist model, yet its effects are unknown. Implementation of comanagement at UCSF will permit the first rigorous evaluation of comanagement and provide a laboratory for this training award. The proposed course of study will augment the Principal Investigator's (PI) existing skills in outcomes research, cost-effectiveness analysis, and clinical epidemiology with methodology useful in the execution of clinical trials, analysis of complex datasets, and organizational theory as it relates to executing and assessing changes in healthcare systems. This proposal also describes 3 research goals, to be achieved in 2 phases. The first phase will involve derivation of a medical complication risk index to identify high-risk patients. Phase 2 will be centered around a randomized trial of comanagement of at-risk patients identified by the index, and will examine comanagement's impact on patient safety (as measured by medical complication rates), utilization, and patient satisfaction. The third goal, to also take place in Phase 2, involves refinement of data collection strategies for use in future multicenter studies. Thus, this award will allow the applicant to develop new skills important to his clinical and research career, and provide the setting in which he will become an independent investigator in perioperative medicine outcomes research and organizational methods to improve perioperative patient safety.